package com.bjsxt.hibernate; import java.util.Date; import org.hibernate.Session; import org.hibernate.Transaction; import junit.framework.TestCase; public class SessionTest extends TestCase { public void testHello1() { System. out.println( " -----------SessionTest.Hello1()------------ "); // throw new java.lang.RuntimeException(); } public void testHello2() { System. out.println( " -----------SessionTest.testHello2()------------ "); // this.assertEquals("hello", "hello111"); } public void testSave1() { Session session = null; Transaction tx = null; User user = null; try { session = HibernateUtils.getSession(); tx = session.beginTransaction(); // Transient瞬时状态 user = new User(); user.setName( " 白龙马 "); user.setPassword( " 123 "); user.setCreateTime( new Date()); user.setExpireTime( new Date()); // persistent持久状态,当属性发生改变的时候，hibernate会自动和数据库同步 session.save(user); // 发Hibernate: insert into User // save执行后：让id=402881e538dc30fd0138dc3189490001 user.setName( " 猪八戒 "); // 发Hibernate: update User set,Hibernate怎么知道什么时候要发update语句呢？ // 它做的是数据版本也叫 脏数据检查 // session.update(user); tx.commit(); } catch(Exception e) { e.printStackTrace(); tx.rollback(); } finally { HibernateUtils.closeSession(session); } // detached状态 // 显著特点：a.没有被session管理，同时数据库中有相应的记录 user.setName( " 七仙女 "); try { session = HibernateUtils.getSession(); session.beginTransaction(); // 又变成了persistent状态 session.update(user); session.getTransaction().commit(); // commit后，发Hibernate: update User set XX ，此时数据库中记录被更新 } catch(Exception e) { e.printStackTrace(); session.getTransaction().rollback(); } finally { HibernateUtils.closeSession(session); } } public void testReadByGetMethod1() { Session session = null; try { session = HibernateUtils.getSession(); session.beginTransaction(); // 马上发出查询sql，加载User对象 User user = (User)session. get(User. class, " 402881e538dc30fd0138dc3189490001 "); System. out.println( " user.name= " + user.getName()); // persistent状态,当属性发生改变的时候，hibernate会自动和数据库同步 user.setName( " 白马王子 "); session.getTransaction().commit(); } catch(Exception e) { e.printStackTrace(); session.getTransaction().rollback(); } finally { HibernateUtils.closeSession(session); } } public void testReadByGetMethod2() { Session session = null; try { session = HibernateUtils.getSession(); session.beginTransaction(); // 采用get加载数据，如果数据库中不存在相应的数据，返回null User user = (User)session. get(User. class, " asdfsafsdfdsf "); session.getTransaction().commit(); } catch(Exception e) { e.printStackTrace(); session.getTransaction().rollback(); } finally { HibernateUtils.closeSession(session); } } public void testReadByLoadMethod1() { Session session = null; try { session = HibernateUtils.getSession(); session.beginTransaction(); // 不会发出查询sql，因为load方法实现了lazy（懒加载或延迟加载） // 延迟加载：只有真正使用这个对象的时候，才加载（发出sql语句） // hibernate延迟加载实现原理是代理方式 User user = (User)session.load(User. class, " 402881e538dc33410138dc335ef30001 "); System. out.println( " user.name= " + user.getName()); // persistent状态,当属性发生改变的时候，hibernate会自动和数据库同步 user.setName( " 白雪 "); session.getTransaction().commit(); } catch(Exception e) { e.printStackTrace(); session.getTransaction().rollback(); } finally { HibernateUtils.closeSession(session); } } public void testReadByLoadMethod2() { Session session = null; try { session = HibernateUtils.getSession(); session.beginTransaction(); // 采用load加载数据，如果数据库中没有相应的数据 // 那么抛出ObjectNotFoundException User user = (User)session.load(User. class, " 55555555 "); System. out.println(user.getName()); session.getTransaction().commit(); } catch(Exception e) { e.printStackTrace(); session.getTransaction().rollback(); throw new java.lang.RuntimeException(); } finally { HibernateUtils.closeSession(session); } } public void testUpdate1() { Session session = null; try { session = HibernateUtils.getSession(); session.beginTransaction(); // 手动构造的detached状态的对象 User user = new User(); user.setId( " 402881e538dc33410138dc335ef30001 "); user.setName( " 刘德华 "); session.update(user); session.getTransaction().commit(); } catch(Exception e) { e.printStackTrace(); session.getTransaction().rollback(); } finally { HibernateUtils.closeSession(session); } } public void testDelete1() { Session session = null; try { session = HibernateUtils.getSession(); session.beginTransaction(); // // 手动构造的detached状态的对象 // User user = new User(); // user.setId("402880d01b9be8dc011b9be9b23d0001"); // user.setName("德华"); // session.delete(user); User user = (User)session.load(User. class, " 402881e538dc33410138dc335ef30001 "); session.delete(user); session.getTransaction().commit(); } catch(Exception e) { e.printStackTrace(); session.getTransaction().rollback(); } finally { HibernateUtils.closeSession(session); } // transient状态 } } ----------------------------------------------------- package com.bjsxt.hibernate; import java.util.Iterator; import java.util.List; import org.hibernate.Query; import org.hibernate.Session; import junit.framework.TestCase; public class QueryTest extends TestCase { public void testQuery() { Session session = null; try { session = HibernateUtils.getSession(); session.beginTransaction(); Query query = session.createQuery( " from User "); query.setFirstResult( 0); // 注意第一条记录从0开始 query.setMaxResults( 4); List userList = query.list(); for (Iterator iter=userList.iterator(); iter.hasNext();) { User user = (User)iter.next(); System. out.println(user.getId()); System. out.println(user.getName()); } session.getTransaction().commit(); } catch(Exception e) { e.printStackTrace(); session.getTransaction().rollback(); } finally { HibernateUtils.closeSession(session); } } }